21905126804 has 12 divisors (see below), whose sum is σ = 41818878528. Its totient is φ = 9956875800.

The previous prime is 21905126767. The next prime is 21905126819. The reversal of 21905126804 is 40862150912.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 248921852 + ... + 248921939.

It is an arithmetic number, because the mean of its divisors is an integer number (3484906544).

Almost surely, 2^21905126804 is an apocalyptic number.

It is an amenable number.

21905126804 is a deficient number, since it is larger than the sum of its proper divisors (19913751724).

21905126804 is a wasteful number, since it uses less digits than its factorization.

21905126804 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 497843806 (or 497843804 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 38.

The spelling of 21905126804 in words is "twenty-one billion, nine hundred five million, one hundred twenty-six thousand, eight hundred four".